A pioneering California law meant to sharply limit use of the familiar “chasing arrows” recycling symbol has been blocked by a federal judge who said it probably violates the First Amendment.

In a preliminary injunction issued earlier this month, U.S. District Judge William Hayes halted enforcement of SB 343 after food, packaging and retail groups sued, finding that key provisions were “unconstitutionally vague” and likely infringed protected commercial speech. Enforcement of the law, passed in 2021, was expected to start this fall.

The decision is a blow to environmental advocates, who had hoped to remove the familiar symbol from a huge array of plastic products, in line with a statewide study showing that only a fraction are widely collected and actually recycled. SB 343 said only goods and packaging accepted by recycling programs serving at least 60 percent of Californians and then actually sorted for recycling — not collected and thrown away — could bear the chasing arrows.

Hayes’ constitutional reasoning surprised supporters of SB 343 because similar arguments against environmental marketing regulations have historically struggled in court.